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Algebra2D

Complex Numbers - Theory & Concepts - De Moivre Theorem

Understanding imaginary numbers, complex operations, the complex plane, and De Moivre's Theorem.

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De Moivre's Theorem Explorer

Complex Number z

z=1.20(cos45+isin45)z = 1.20 \left(\cos 45^\circ + i \sin 45^\circ\right)
z=1.20ei0.785z = 1.20 e^{i 0.785}
Magnitude r (Radius)1.20
Angle θ (Degrees)45°
Power nn = 3

Theorem Application

Result: znz^{n}
z3=1.203(cos(345)+isin(345))z^{3} = 1.20^{3} \left(\cos (3 \cdot 45^\circ) + i \sin (3 \cdot 45^\circ)\right)
z3=1.728(cos135+isin135)z^{3} = 1.728 \left(\cos 135^\circ + i \sin 135^\circ\right)

Notice that the magnitude raises geometrically to 1.728, while the angle multiplies linearly to 135° (or 135° coterminal).

ReIm0.511.522.5zz2z3
z (Original)
znz^{n} (Result)
Intermediates